1. Field of the Invention
The present invention relates to bacterial complexes which may be used in the digestion, the decomposition and the transformation of residues of biological origin in the form of biomass and of stable, non-polluting organic compounds and to their applications to the treatment of waste of biological origin, such as excrement (pig, ruminant, equid or poultry litter or human excrement, liquid manures) or liquid manures, corpses, stagnant waters and their conversion into compost or other stable, biodegradable and non-polluting nitrogenous compounds.
2. Description of the Background
Heterotrophic organisms use nitrogenous compounds, including plant or animal proteins, as nutrient sources and return the nitrogen to the soil via their excreta or via post-mortem decomposition products, mainly in the form of aqueous ammonia or urea which are converted into nitrites and nitrates by nitrifying bacteria present in the soil, such as Nitrosomonas or Nitrobacter.
However, substantial production of nitrogenous compounds in gaseous or liquid-solid form, such as ammonia gas, aqueous ammonia, nitrites and nitrates, constitutes an important cause of atmospheric pollution and of pollution of soils, water courses and water tables. All of these processes of destruction lead to the formation of compounds with particularly nauseating odours (NH.sub.3 and H.sub.2 S in particular, etc.).
Processes are known for the treatment of liquid manures, litters or waste waters, which involve a bacterial culture and enzymes or a bacterial culture, enzymes and yeasts, in order especially to reduce the evolution of ammonia and odours, particularly at the time of handling and during spreading (liquid manure). Such compositions contain in particular, as bacterium: Bacillus subtilis, as enzymes: batinase and amylase, and as yeasts: Saccharomyces cerevisiae (French patent application 2,658,077).
However, the compositions known for treating excrement do not allow the conversion of inorganic nitrogen (NH.sub.4, NO.sub.2 and NO.sub.3) and urates into amino acids and proteins (organic nitrogen) but merely reduce the evolution of ammonia, by adsorption or solubilization. Such conversions do not lead to a reorganization of the nitrogen, by its use at the level of the nitrogenous metabolism of microorganisms.
Consequently, an effective treatment of products of biological origin is necessary and crucial in order to allow the conversion of inorganic nitrogen (NH.sub.4, NO.sub.2 and NO.sub.3) and urates into organic nitrogen (amino acids and proteins), in order to prevent pollution and to return the waste into the circuit of anabolism.